Re: Compressing folders/sub-folders with TAR : how to ?

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Date: Wed, 26 Jan 2005 17:47:18 +0000

2005-01-26, 06:57(-08), A Web Master:
> What's the syntax to compress all folders and sub-folders found with TAR ?

tar is not a compressor, that's an archiver. tar makes an
archive, it provides with a stream of data containing the
representation of a directory tree.

Compression is the job of other tools like gzip or compress or
bzip2 whose role is to take an arbitrary stream of data as input
and produce a compressed stream of data as output.

tar cf - . | gzip > ../file.tar.gz

creates a compressed archive of the current directory (.) stored
in the ../file.tar.gz file.

3 tools were contributing in making that archive:

1- the shell that created and opened the file for writing and
launched and connected the two other tools together.

2- tar that produced the archive stream on its standard output
(with the -f -, otherwise by default, tar would put that stream
on a tape as it's a Tape ARchiver).

3- gzip that read the data from its standard input (that was
connected to tar's standard output via a pipe created by the
shell (and managed by the Unix system)) and wrote the compressed
data on its standard output (that was connected to the file by
the shell).

That's a simple example of how you can combine simple tools
together to have them perform a more complex task.

-- 
Stéphane

• Previous message: Bill Marcum: "Re: Compressing folders/sub-folders with TAR : how to ?"
• In reply to: A Web Master: "Compressing folders/sub-folders with TAR : how to ?"
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